Disclaimer: I do not own Warhammer 40,000 it is owned by Games Workshop.

Disclaimer: The Roboutian Heresy is a FanFiction penned by Zahariel. I have received permission from him to set this piece within the universe of The Roboutian Heresy.

Blood of Ignorance

Prologue

Artaxerxes could see it with his inner eye.

The skies over the world were diseased, as a million colours of every shade imaginable and a million other shades that did and could not exist in reality swirled in a blazing riot over the planet's atmosphere. Corposant crackled in the atmosphere, aurorae flickering madly as lightning flashed and thunder boomed.

It was – as one of the Emperor's Children would put it – a terrible but no less grand overture to something to come. The atmosphere was heavy with anticipation, bleeding through time and space through the Warp to touch Artaxerxes' vision.

As reality buckled and heaved overhead, war provided an accompaniment below. Hovercraft hummed fast and heavy over the ground, ignoring the tank traps dug and mines laid down by the heretics. Their slender, fish-like forms shrugged off laser bolts and bolt rounds without care, brushing aside barbed wire as burst cannons showered plasma death over the trenches. Rockets soared overhead and slammed into earthworks, sending dirt and bodies flying into the air.

Even in the distance, Artaxerxes could see the corruption evident in the flesh of those manning the earthworks. Some had scales in place of skin. Others had tentacles where limbs should be, beaks in place of mouths, and more eyes than a Human should have.

Rockets flew back from the heretics' lines. They had dug in on a cluster of hills in the base of a mountain range, their fortifications' robust construction indicating long preparation and planning having been put into action.

Artaxerxes saw it then, visions within visions, of dark and terrible rituals in the night over a period of months, hundreds of sacrifices offered up to the gods of Chaos that carved a crest of blood into the world that echoed into the Warp. And the Warp answered.

Something was coming. Even across time and space Artaxerxes could feel it through the Warp, the Veil tearing and reality buckling and groaning as something that should not be, a being of principle seeking form in a realm wherein it had no place, struggling to break through and become real.

The heretic rockets struck the fish-like vehicles, most of the vehicles shrugging them off with only minimal damage. One however went up in a ball of fire, and another crashed into the ground, belching black smoke into the air.

Humanoid forms poured from the ruined vehicle and others like it, the Fire Warriors going to ground as laser and heavy bolter fire lashed out at them. Their armour appeared similar to Imperial carapace armour, though no pattern of advanced headgear that Artaxerxes knew of featured the vertical optics bank their helmets possessed.

And neither did Humans nor any recognized abHuman strain possess four-fingered hands as a matter of course.

He already knew what they were. He didn't need to see the unit patches on their armour, or their strangely-rectangular, long-barrelled plasma weapons, or even the design of their armour to tell them what the humanoid warriors were. He didn't even need to notice their four-fingered hands, or the blue blood that poured from their wounds and corpses, or even their 'Devilfish' transports that he recognized from a few engagements in the past.

He knew. He simply knew they were Tau from the very beginning, the truth revealed to him nonverbally by the Warp, any corruption filtered out by the Rubric, his own intellect, will and judgment, honed to a fine edge by centuries of experience and the inherited wisdom of ten thousand years.

Mortars could be heard in the distance, and a series of explosions tore up the Tau positions. The Tau returned fire, Skyrays in the distance silencing the heretic artillery. The Tau advanced by fire and movement, but going was slow, the heretics' interlocking heavy bolter positions inflicting heavy losses on the Fire Warriors, the Devilfishes' support slackening as the slowed advance allowed the heretics to use rockets more effectively.

And as the vision progressed, he knew too what was happening. The Tau in their ignorance of the galaxy's dark and the price of naïve idealism had allowed their so-called 'Human helpers' to fall to the Great Enemy's temptations, and to hide their corruption until it was too late.

The ruined but excavated and partly-restored temple in the middle of the heretics' positions was proof of it, just as much as the shimmering haze of light and shadow proved the heretics' nefarious designs were nearing completion.

They came from the skies, soaring down on wings of fire. Their bulky and hulking forms lacked the familiar visage of assault marines such as those fielded in assault squads or invidual Astartes jump pack specialists, but Artaxerxes could concede – no matter how grudgingly – that the Tau Crisis Suits had their own terrible grandeur.

He had seen and fought them before, and warriors respected other warriors.

Flamers and missile launchers roared as the Crisis Suits punched through the heretic lines like a sword striking a head off. Rockets exploded harmlessly against their armour, or were avoided by the surprisingly-nimble Tau war machines. Laser fire and bolter fire broke like waves against rock, and heretics died screaming in flames or rippling explosions.

As the heretic lines broke, the Tau infantry advanced by fire and movement, Fire Warriors covering their fellow Fire Warriors as they moved to cover and then provided cover for their fellows as they too advanced in their turn. The Devilfish stayed close, burst cannons blazing with plasma fire as they provided heavy fire support.

Artaxerxes looked on as the Tau fought their way to the temple, plasma blasts and missiles levelling the ancient ruins as they sought to reach the ritual grounds. And he saw it. A great circle broken at eight points by the eight-pointed star of Chaos Undivided, each point holding aloft a crucified psyker, blood pouring from their tortured forms to fill the grooves cut into the ritual grounds.

Artaxerxes wanted to scream, to force the Tau to stop, as he saw them walk right into the heretics' trap. Xenos or not, what was to come was a fate he would not wish on any living being.

Death and oblivion were merciful compared to falling into the hands of the Ruinous Powers.

A circle of cloaked and hooded heretics bowed and chanted in-sync, facing inward along the edges of the circle, while in the centre wreathed in corposant stood a priest of Chaos. Like its fellow cultists it was cloaked and hooded, but where hands should have emerged from his sleeves a pincer and a claw emerged, and instead of a beard a writhing mass of tentacles hung down from his hood.

The leading Crisis Suit broke the circle, and bathed it in flame. A thousand and one sacrifices had been offered to the Warp, and the Veil could take no more.

Time stopped. It was only for an instant, but Artaxerxes knew in that instant that the ritual was complete. As one, the cultists screamed, and then blinding light flooded the circle and immolated all within as the crest of blood was completed. A pillar of light and energy erupted with a thunderous roar up into the sky, buffeting aside the corposant and energy rippling through the atmosphere and the streams of Warp energy leaking into space.

After several moments the light faded, revealing a Humanoid form floating high over the temple. Only, Humans didn't float. Also, Humans didn't have flawless, smooth, reflective and glowing skin of pure gold. And finally, Humans did not have burningly-bright, perfectly-circular and expressionless eyes of white.

The moment stretched, and then the remaining Tau levelled their weapons. They couldn't fire. The being twitched a finger, and they were frozen in place. It raised its hands, palms open and held upwards, and then the Crisis Suits and vehicles crumbled to dust, pilots and crews rising up into the air along with Tau infantry and heretics alike.

White streams began to stream from the floating figures, drawn into the open hands of the Daemon Prince. They shrivelled like husks, flesh aging rapidly and unnaturally, until they were mummified corpses hanging in the air. The Daemon Prince didn't move. They fell to the ground, and then the Daemon Prince stretched its arms wide.

Blazing light erupted in a great fountain that stretched forth from the Daemon Prince, reaching out to every sapient being on the planet. Most died in an instant, the flesh stripped from their very bones leaving only bleached bones to fall to the ground.

They were the lucky ones.

The stronger-willed survived, most only to have their flesh flow like wax and their screams turn to insane gibbering or animalistic sounds as their souls were either ripped to shreds or cast out into the Warp to be devoured by hordes of waiting Neverborn. More others yet survived, avoiding the fate of spawnhood to bear witness as an entire world was consumed by the Warp.

And then the Daemon Prince let loose its power, plunging the world into the Sea of Souls.

Artaxerxes awoke, gasping and heaving, the crystalline doors of his meditation capsule opening at his awakening. The Thousand Son staggered out, serfs and servitors attending to him. He stripped off his sweat-soaked robe, and replaced it with another.

"Inform Brother Cyril…" he ordered one of his brothers who stood vigil in a circle around the meditation capsule. "…the Great Enemy stirs, drawn by the folly of the ignorant and the weakness of the lacking among Mankind. And inform our guests as well."

Artaxerxes swept a hand over his brow as one of his brothers nodded and sent a telepathic message to the leader of the cabal and then to the Inquisitor they were currently hosting. In hindsight Artaxerxes could have done it himself, but he needed to anchor himself first. The Rubric's protection was not absolute, and it would be prudent to assume that the vision he had received carried at least a small amount of taint. He would have to reflect on his actions, examine himself, and shore up the defences of his mind and soul alike.

Only then could he be certain of his continued psychic purity.

"The Tau in their ignorance will allow the servants of the Dark Gods to enter this realm." Farseer Macha addressed the leaders of Craftworld Biel-Tan. "On a world once ruled by the mon'keigh Imperium, since taken by the ignorant children of T'au, weakness and folly will bring forth a tide of evil. A prince of the Neverborn will come forth, and cast the world into the Sea of Dreams. From thence it will return in a hundred years and a day, and birth a festering sore in the very fabric of reality, from which evil and horror will spill forth. This cannot be allowed."

As the Farseer finished, one of the exarchs of Biel-Tan's Howling Banshee shrines stood. "Your concerns regarding the Great Enemy are understandable, honoured farseer." The exarch said. "However we do not possess the strength to answer every threat, nor can we afford to do so. Should we not focus our attention on those threats which threaten our craftworld, and the rest of our kin? Even as we speak, a foul tide of greenskins makes its own to a collection of Maiden Worlds along Lilean's Path."

Agreement echoed from the Council of Autarchs and the Court of the Young King. The Seer Council stayed silent however, and it was another farseer which spoke up next. "It cannot be denied that our primary focus should be on the greenskins threatening our kin along Lilean's Path." He said. "However the council has meditated on Farseer Macha's visions and we have ascertained an eventual threat from ignoring it."

He stretched forth his hand, and called forth images of daemons and their corrupted minions fighting against Astartes and Human soldiers. "In time…" the farseer said. "…the return of the corrupted world will be the cornerstone of a corrupted realm, from which a threat will rise to the prison the Anathema's descendants have erected against their corrupted kin."

The images shifted, showing now the Eye of Terror and the Imperium's fleets and armies being driven back, Cadia burning, and to the horror of the Eldar, Ulthwe protected only by the desperate valour of both their fleets and those of the mon'keigh. "This threat shall split the mon'keigh's strength…" the farseer said. "…and weaken the watch they have placed over the corrupted ruins of our empire. The servants of the Dark Gods will come forth at the same time and in the worst case…"

The farseer trailed off, letting the images of Ulthwe burning and breaking, Terra under siege once more, and a tide of demons spilling unstoppably over the galaxy speak for themselves. For a time after the images the Eldar sat silent, cycling their emotions back into balance, and once again Macha spoke.

"The Imperium has not the strength to move against the Tau at this time, their attention drawn by the Great Devourer's advances." She said. "We may warn them yes, but I fear that with their primitive Warp drives even their Inquisition will arrive too late."

"And the mon'keigh being mon'keigh…" an autarch snorted derisively. "…even if they arrive in time they are as likely to make a mess of things as they are to resolve it. And that assumes those mammals would pay heed to our warnings."

"Indeed…" Macha admitted. "…but the Tau are in no way better than the mon'keigh."

"What do you plan to do farseer?" the Young King asked, his words silencing all else.

"Our focus must be against the greenskins." Macha said. "But I ask permission to take a small force with me to deal with the threat. To minimize the risk of precious Eldar lives lost, I shall warn the Tau first of the evil that slumbers in their midst, though it is unlikely they will pay heed. In that case, I will do what I must."

A thoughtful silence filled the air, and then as it began to grow oppressive the Young King spoke. "The council will now deliberate." He said, and Macha bowed before leaving, abstaining from participating in the deliberations due to her personal involvement in the matter.

As she left the council chambers, the doors closed shut behind her with an ominous air.

A/N

And here we are, a story set in the universe of Zahariel's The Roboutian Heresy, wherein the traitors of canon are the loyalists. A cabal of the XV Legiones Astartes and their Inquisition allies move against a Chaos threat on an unsuspecting Tau world, not knowing the Eldar of Biel-Tan intend to do so as well…and vice-versa.

Beta'd by Zahariel, thank you and thank you again for letting me set this piece within your alternate Warhammer 40,000 universe.